0:38 "I want to try and keep this as accessible as possible..." 5:20 "... a seven-dimensional hyper-cube" I could listen to this man for hours, but did I miss something in the middle there?

@rana4410

4 жыл бұрын

I would say you missed about 4:42 of the video

@SellamAbraham

4 жыл бұрын

@@rana4410 I would say you missed @8:27.

@nachoijp

4 жыл бұрын

Well, he said he wanted to try, not that he'd succeed

@Xvladin

Жыл бұрын

I don't think saying "hypercube" is that inaccessible. It's just a cube but in higher than 3 dimensions.

@jhonbus

11 ай бұрын

😂😂 To everyone disagreeing: you're arguing with a joke.

Meanwhile, inside the computer... "Sir, we got the message." "Is it Yes or No?" "Well, it's kind of neither. Something's wrong." "Okay, well, map it into hyperdimensional space then get back to me."

@paulmag91

7 жыл бұрын

On point!

5 жыл бұрын

count the zeroes and the ones and tell me which is more, that will win

@firstnamesurname6550

5 жыл бұрын

ROFL

@Friek555

5 жыл бұрын

If it's a hypercube then the message is more than one bit, so not just Yes or No

@pilotavery

4 жыл бұрын

"Sir... I think it's a quantum bit"

man this dude should make computer science documentaries, his voice is engaging

@Joshua-ym7ei

7 жыл бұрын

I was just about to comment how i don't know what it is entirely, but i like this guy haha

@tuneboyz5634

3 жыл бұрын

shut up

@donquixoteupinhere

2 жыл бұрын

Yeah man he should start teaching or something ¯\_(ツ)_/¯

@FilSapia

2 жыл бұрын

He is basically the David Attenborough of Computer Science :)

prof.Brailsford is david attenborough of computer science even sound like him

@MatthewHarrold

7 жыл бұрын

Ha! I was just thinking the same.

@benjaminbrady2385

7 жыл бұрын

VIJeTH Poojary true

@TomatoBreadOrgasm

7 жыл бұрын

Even sort of looks like him, but then they are both elderly Brits.

@SteveParkin

7 жыл бұрын

Yes, this professor is one of my favourites on this channel. Let's try and reason why it's perfect by waving our hands around ... a lot.

@simoncarlile5190

7 жыл бұрын

Here we see the hypercube in its native habitat as it scavenges for food

Long live and prosper, Professor.

@kellykitkat40

7 жыл бұрын

Live prosper and long?

@clayton8or

7 жыл бұрын

Prosper long and live?

@stokesy887

7 жыл бұрын

Dave Null and long live prosper

@AfonsodelCB

7 жыл бұрын

long prosper live and.

@paulmag91

7 жыл бұрын

prosper and long live

Could you start over? I missed the part where everything was explained

@KnakuanaRka

4 жыл бұрын

KittenKillzU Long story short, this is supposed to be part of a series, not seen by itself. They should have mentioned it somewhere.

And, 313 is the licence plate number of Donald Duck.

@Keyakina

7 жыл бұрын

Now THATS something I understand!

@ZLau13

7 жыл бұрын

INSANE NL Nice. Used to read tons of Donald Duck comics as a kid.

@Zupernova91

7 жыл бұрын

That was my first though as well :)

@mickelodiansurname9578

7 жыл бұрын

INSANE NL Donald duck is so two dimensional...

@neshmicc

7 жыл бұрын

Also the area code for Detroit.

I'd love to see you explain Reed-Solomon error correction. They're used everywhere and are very interesting from the maths side of it. The BBC have an amazing paper on the topic and have a neat example with a toy RS(15,11) code setup - but it still took me an insanely long time to wrap my head around the decoding side of it.

@daniellewilson8527

10 ай бұрын

What’s the name of the paper?

For what I am understanding from this is: use 3 bits to represent 1 bit, so its ultimate data remains the same as its initial data when copied or moved. Imagine sending the value of 0 as 000, then one of its bits gets corrupted so that it displays 010. When the receiver gets 010, it is supposed to assume that it was 000, since it has more 0's than 1's. After that, the receiver would translate 000 to 0.

07:01 the definition of 'perfect code': "That is what a perfect code is all about; it's about using up the corners on your hypercube to the absolute maximum." ... I wish I knew this when I started programming :D

@eidiazcas

3 жыл бұрын

This deserves way more likes

Trying to imagine 7 dimensional space is kind of a non-starter.

@lincolnpepper816

4 жыл бұрын

you don't need to imagine 7 dimensional space to understand this video

@akinoreh

4 жыл бұрын

​@@lincolnpepper816 _continued_ : ... if you didn't plan understanding the video in the first place.

@MarshmallowMadnesss

4 жыл бұрын

It's heavy, but an adequate understanding of binary and a vague grasp of programmatic looping helps a little. A second watch also helps. Either way, I am in awe of this guy's knowledge.

@crazydog3307

2 жыл бұрын

its not that hard

@markuspfeifer8473

Жыл бұрын

Just imagine an n-dimensional space and then set n=7

Should've started like this: "First, imagine a 7-dimensional cube ..."

Best explanation of hamming code correction I've ever seen. I already knew how it worked but now I really understand it - Brilliant stuff!

+Computerphile, please please please list the earlier videos this series, at least in the description. When reading through the comments it's obvious that this video by itself makes little sense to many viewers, and the title doesn't really reveal that it is a part of a series either.

@bennylofgren3208

7 жыл бұрын

ProfDaveB Thanks! Love the content as always. :-)

I love Professor Brailsford, he always captures my love for computer science with his soft spoken explanations and anecdotes. source: developer

6:25 gotta love this good old chap, Prof Brailsford got me hooked on Computerphile back in the days.

Every time I hear professor Brailsford speak he blows my mind. 10/10

I was really having a hard time doing my Coding Theory assignment as I was having hard time connecting Hamming codes with Hypercubes. This helps

I have no idea what this great man is talking about. Thought the video was writing the perfect computer code.

@tobiasgertz7800

4 жыл бұрын

Error correction codes in electronic communication

0:27 those 2 buttons are stronger than all relationships I've been in.

Hamming codes notation meaning explained well, and that there exist many Hamming codes, and that Hamming codes can only correct single error. Plus their nice usage 'density'. I also recommend to look at hamming bound formula V(n,t) and also size of t-error-correcting code to understand whole explanation of numbers 8, 16, and 128.

The 'Perfect Code' is only perfect in a perfect scenario and in this world there is none. ~ Edge Hog

@IronicHavoc

3 жыл бұрын

It's just a name

I love that as I watch this I THINK I understand, but in no way can I apply this personally. Haha.

@MrGoatflakes

7 жыл бұрын

Why not? You might need to some time transmit some data reliably in one of your projects. Or make a way to store your files that is tolerant of errors.

@HansPeter-qg2vc

7 жыл бұрын

He's saying that he would not be able to implement it or be able to pass an exam testing his knowledge about it.

@lazarstojanovic1915

7 жыл бұрын

You don't need this in every day coding , but it might prove useful in the future

@GFlCh

7 жыл бұрын

+MrGoatflakes - "Why not? You might need to some time transmit some data reliably ...". Realistically, if I needed to send it reliably, I'd use an error correction (EC) scheme that would protect against multiple bit errors. The "EC" in this video (Hamming Code) is for trivial cases at best. Perhaps a case where the EC is performed entirely with hardware (gates/flip-flops...) or where the scheme is used for only for error detection, along with re-transmission.

@onceuponfewtime

6 жыл бұрын

after rewind the video a couple of times, I am proud to say I have understood this perfect code hehe

My man needs a bigger shirt

@TheRovardotter

7 жыл бұрын

That shirt button is getting a workout

@kaoti

5 жыл бұрын

@The Absolute Madman and you need a bigger brain.

I could listen to this man talk about computer theory for hours.

I love this series on error correction

This video was easier to follow than most others in this section, despite the hypercube. Does a ball with cut edges to produce those corners fit as an illustration?

I love listening to him. Such a nice person.

This guy is so enjoyable to listen to. :D

that cube animation reminded me of the code deciphering scene from the movie 'Contact'.

Finally a new video! I had signs of withdrawal.

I swear something extremely similar was discussed in the computerphile video about sending compressed messages and digital compression in general.

Reminds me of neural networks coalescing a pattern of neural inputs into one response, or output. i.e. in the case of a 7-bit 'perfect code' it would be outputting a 4-bit response... This also reminds me of sparse distributed vectors and Hierarchical Temporal Memory.

So if I understand this correctly it is essentially: The alternative is the transmit both the original and OR version for verification, AND them both, if results to zeroed bytes, pass, if failed, re-transmit... So a 8bit message requires 16bits transmitted and twice that again if it fails, NACK if you prefer. With this method, the datagram is essentially computationally self correcting resulting in no re-transmission?

When will the ytp come?

Another challenge is determining which bit is in error. The point is moot for one bit of data transmitted. For data comprising more than one bit, you need to determine which bit or bits flipped during transmission. Identification of the position of the erroneous bits requires more complex or more sophisticated codes.

Better explanation than previous video

I want this man to explain to me everything in life

Alright, so the perfect codes are Donald Duck’s car (2:47) and a Touhou boss battle (5:48). Did I get it right?

@NoNameAtAll2

7 жыл бұрын

Touhou fans unite

With 3D printing can the computer builders make more efficient shapes generated via 3D drawing tool using fractal filters or other type of shape generators.

What if we use these Hamming's error correcting codes together with the same technique as balanced cables use, where the same signal get sent twice (on two different cables), but one of them is reversed. Then you would reverse the bits on one of them back and then compare them bit by bit. If there's any changes, you know that you have errors.

How about a collaboration with your Numberphile channel and do a video about the Fast Inverse Square Root function? That would be amazing!

@giuseppeugo2716

7 жыл бұрын

thatusername a video on the Power of two?

@frostyusername5011

7 жыл бұрын

The thing how a binary floating point number, when treated as an integer and the bits shifted once and subtracted from a constant, following a round or two of Newton's method, gives a rough approximation for the inverse square root. IE: 0x5f3759df

I just realized that "Computerphile" is an oronym for "Computer File"

@tj8870

5 жыл бұрын

"Suffixes with the common part -phil are used to specify some kind of attraction or affinity to something".

@novelnouvel

5 жыл бұрын

@@juanmanuelespanabolacuenta4048 You win. Now get out. 😂

@skylarkenneth3784

5 жыл бұрын

@@juanmanuelespanabolacuenta4048 Peta File

@claudesedillo2828

4 жыл бұрын

Not even close

Man I love computerphile

@hassiaschbi

7 жыл бұрын

so, you are computerphilephile?

@3117master

7 жыл бұрын

I like people who like computerphile. that would make me a computerphilephilephile

@lazarstojanovic1915

7 жыл бұрын

I like people who like people who like computerphile , that makes me a computerphilephilephilephile

@adamfirth3082

7 жыл бұрын

moment of silence

These codes only detect and correct one error per transmitted message but couldn't you somehow get an estimate on the errors in some process and stack these codes somehow so they all correct some part of the erroneous whole?

I like the concept of fountain codes; generate a practically infinite set of error correcting chunks, until the reciever is able to respond "i got it" -- with very high probability, if you have a message N chunks long, then any N+1 chunks out of the original data and the "error recovery" data can be used to recover the original message. The cool thing is there is no limit to the amount of extra error correcting chunks able to be generated ; unlike a hamming code where there is only 1 way to transmit the message. That way you can perfectly tune your transmition for the error rate of the channel;

I think I don’t fully understand this but at the end where he said they could only detect one error, what if there were a bunch of hyper cubes all connected? And each one detected one error.

5:11 Based on the pattern, I'd say that the n-th "proper" Hamming code is 2^(n+1)-1 bits in length.

The shortest distance between two points A and B is a straight line. (euclid-space, 2D) The minimum Hamming distance of a code is the smallest distance between two (different) words in the code. (hyper-space, 4D)

Now the question is: in which scenario should this be implemented?

Hey guys do you have something to say about mean shift clustering and its initialization , i'd like to hear about it.

I hv one question. So it's redundancy ryt 0-> 000 n 1->111 so it's 1 bit data

You should explain that the procedure of going to the nearest corner reflects the notion that is there is a greater probability that one bit flipped in transmission than two or three bits.

hey would it be possible to ask u a question about computers Computerphile

Do you think tasing myself in my third eye my pie Neil would actually activate the DNA faster curious question would the electricity activate in the fullerene particles to expand quicker

What exactly is the middle bit? He said something like the number of those bits that evoke into the real message. In [7,4,3], what does the 4 mean?

@rustygear447

7 жыл бұрын

if i understand it correctly [3,1,3] you're sending a total of 3 bits of data to convey 1 bit of message. [7,4,3] you're sending 7 bits in total to convey 4 bits of message.

@tigergoldfish17

7 жыл бұрын

How would 7 bits convey 4 bits of message?

@bennylofgren3208

7 жыл бұрын

tigergoldfish17 That's the whole point of Hamming codes. With seven bits, you can protect four data bits from one-bit corruption and detect two-bit corruption. With 15 bits, you can protect 11 bits of payload, with 31 one bits you'll get 26 data bits safely across (within the constraints I mentioned). There are several earlier videos on this topic that are more or less required viewing if you are to understand this concept without prior experience, but they were unfortunately not mentioned in the video or description.

@rustygear447

7 жыл бұрын

tigergoldfish17 In [3,1,3]: to send a [1] you send a packet of 3 identical bits [111]. this way, if one of the bits is corrupted it would become one of the following [011], [101], [110] and you can assume that the majority bits are the real message. That also means this method only works when the corruption is no more than 1 bit. In [7,4,3]: to send the 4 bits data, you first need to look up the 7 bits *codeword* from the hypercube map like shown in the video. this codeword guarantee that it is 3 distance away from all other codeword. this is the same as with the [3,1,3] except in [3,1,3] it's much easier to visualize since it's only 3d cube. The rest is the same, you send the 7 bits codeword, and the receiver will take the code and match it to the closest node in the hypercube to find the 4 bits of data you want to convey. again, it only works if the data doesn't corrupt more than one bit. This also means the higher bits it goes, the more unreliable this method becomes as the more bits you send, the more likely it'll get corrupted more than 1 bit.

@WrenAkula

7 жыл бұрын

+tigergoldfish17 Because you have 16 seven bit code words, each of which maps to a unique 4 bit message.

Very interesting! I love learning about new concepts like this? :D

Why is it that these only occur with higher dimensional cubes. Could other Platonic solids like a tetrahedron work, or for that matter any polyhedra?

and this can be used in code transmission how? lets say i create a chat client on an unstable network. how does this help?

What does the notation [3,1,3] mean?

so when you are correcting a 4 bit message do you still have to send the entire message 3 times? if so and you can only correct 1 bit then why send in chunks of more than 1 bit? as you may as well just send each bit 3 times and use the 2/3 majority. as then as long as long as no more than 1 out of 3 bits for a single bit sent are corrupt every bit could be corrected perfectly, but if it takes 12 bits to send a correctable 4 bit message then there is a much greater chance that more than 1 of the 12 bit sequence could be corrupted. or did i completely miss something?

@dannygjk

6 жыл бұрын

It's more time efficient to send the bits in a group in one packet.

Ok, i get why it cant be even, because if you have 2n bits then if n are 0 and n are 1, then you would not know if it were 0 or 1, but if its odd, there could either be more 0's or more 1's making the one with more apear to be most likely that one. what am I missing?

but at the very end he explains how they're NOT perfect ... so what are the better error correction algorithms?

Hi guys, You guys should talk about the CD, it's got a lot of cool features, one of them being Hamming correction. ... And it's got it all. Why 44k Samples/s ? -> twice the bandwidth of sound (20 - 20kHz)... So 28 bits per sample, it's stereo, so 14 bits each. 10 for the value, 4 for error correction (If I remember well) Lots of cool aspects :)

What if you then transmitted 3 3-bit hamming codes? Then you'd be correcting for each individual bit and reducing the chances of larger errors.

Reminds me of the networking from the map colors video.

Is this guy also the narrator for every BBC wildlife documentary I've ever seen?

@randallanderson4999

6 жыл бұрын

No, that would be Sir David Attenborough, who is the narrator for the BBC wildlife documentaries.

That is some great notation paper. Wondering where they still sell this.

@randallanderson4999

6 жыл бұрын

Check e-bay for "line printer paper", or "Continuous Feed Paper".

Can someone please tell me what type of paper was the professor writing on, cause i'm trying to look for it but I can't find it?

@randallanderson4999

6 жыл бұрын

Fan fold, line printer paper. Came 5000 sheets to a box.

"It's so Eco-friendly." Indeed, sir.

Hamming code is also used in RAID2. A RAID level that is rarely used.

its funny cos the more error correction bits you put in the higher your probability that one of those bits can become corrupted, i think you really needs a checksum logic which resends the packet

I understand that you want to have messages in the protocol. What I don't understand is the correction. Why do you need correction? ty

You know, I could make an argument for a playlist including all these Hammond Code related videos.

@bjornolson6527

4 жыл бұрын

Frank Harr Hamming

its pretty interesting, but i have to wonder why this is used instead of just receiving and interpreting all data, mutated data would obviously fail the check, and produce an error message indicating that the message was either not received or misreceived, at which point the receiver would wait before sending an acknowledgement, and the sender, not receiving an acknowledgement, would resend the information

How does this compare to memory's parity bits? Is this better or more efficient in some way?

@randallanderson4999

6 жыл бұрын

Most memory parity can only 'Detect' one bit errors.

11 days after Buckminster Fuller passed away and 112 Years After he was born on 7-12-1895

The most amazing thing is I actually understood all that.

is this use in LoraWAN protocol?

What's the next video. These codes only correct one error. He mentioned you needed something more robust. What is more robust?

3:40 "313... >_> hmm..." cracked me up.

Liking this video makes me feel smart. edit: I also liked my own comment.

@sudoLife

5 жыл бұрын

perhaps you're from Reddit

That thumbnail has a high power level

How should it work for quantum computer?

you can tell by the size and shape of this man's skull, that is brain is absolutely massive!

love this guy

[9,2,9] would work as a very robust solution?

I sure pray that brailsford lives to 115 or so.

perfect explaination !

this man is brilliant

Pretty much on par with a parity check but with error correction (that requires more transistors to implement..)

what if two bits got flipped? or all three?

I love this guy

The art of computer programming.

I am coming at this for the first time.. thanks!

In what context is this? Is this about when code is transmitted over the internet?

I don't understand. How can you correct your 4 bit message from only 7 bits including the message? Why wouldn't you need 12 bits like how 3 times as many are needed for the first one.

@NoriMori1992

7 жыл бұрын

Luke Rustin It scales up in a different way than what you're assuming.

@profdaveb6384

7 жыл бұрын

Watch "Multidimensional Error Correction" followed by "Correcting those errors" and then, all being well, you'll understand how it's done.

I need to learn this stuff

I love this fellow

This is magic